Gas-fired heater



FIG. 1 is a top, front and right side perspective view of a gas fired heater showing our new design;

FIG. 2 is a front perspective view thereof;

FIG. 3 is a right side perspective view thereof;

FIG. 4 is a left side perspective view thereof; and

FIG. 5 is a top perspective view thereof.

The broken-line showing portions of the rear of the housing are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a gas-fired heater, as shown and described. 